JavaScript Tutorial

JavaScript is the most powerful and versatile web programming language. It is used for making the websites interactive. JavaScript helps us add features like animations, interactive forms and dynamic content to web pages.

In this JavaScript Tutorial, we’ll learn all the basics to advanced topics and concepts of JavaScript. This JavaScript tutorial includes operators, control flow, functions, objects, Asynchronous JavaScript, Events, DOM manipulation, OOPs, Closures, Event loops etc.

What is JavaScript?

JavaScript is a programming language used for creating dynamic content on websites. It is a lightweight, cross-platform and single-threaded programming language. JavaScript is an interpreted language that executes code line by line providing more flexibility. It is a commonly used programming language to create dynamic and interactive elements in web applications. It is easy to learn.

JavaScript Tutorial

Hello World Program in JavaScript

This JavaScript Compiler is completely free and easy to use. Here, you can practice various JS Exercises.

console.log("Hello World! I Don't Give a Bug");

Output:

Hello World! I Don't Give a Bug

Prerequisites to learn JavaScript

HTML: Learn the fundamental of HTML to create structure of web page.

Why to learn JavaScript?

JavaScript is an essential programming language for web developers to learn as it grows rapidly. JavaScript is responsible for behaviour of the web pages. By learning it, you will develop skills in web development.

Key Features of JavaScript:

1. Versatility: JavaScript can be used to develop websites, games, mobile apps, and more.
2. Client and Server-Side: With frameworks like Node.js and Express.js, JavaScript is now used for building server-side applications.
3. End-to-End Solutions: JavaScript enables developers to create complete solutions for various problems.
4. Constant Evolution: JavaScript continually evolves with new features and standards.
5. Vibrant Community: A large community of users and mentors actively contributes to JavaScript’s growth.

JavaScript Basics

Let’s Explore JavaScript’s fundamentals: variables, data types, operators, and control flow for web page dynamism.

• Introduction to JavaScript
• History of JavaScript
• JavaScript Code Execution
• Console in JavaScript
• JavaScript Versions
• JavaScript Syntax
• JavaScript Comments
• Where to Put JavaScript in HTML
• JavaScript First Program Hello world
• JavaScript Data types
• JavaScript Variables
  • let Keyword
  • var Keyword
  • const Keyword

JavaScript Control Flow Statements

Conditional Statements and Loops in JavaScript (Using if…else structures and loops (like for and while) to control program flow based on conditions and execute code repeatedly).

• JS return Statement
• JS break Statement
• JS continue Statement
• JS throw Statement
• JS if…else Statement
• JS switch Statement
• JS try…catch Statement

JavaScript Loops

Repetition Made Easy (Navigate for, while, and do…while for Efficient Code).

• JS for Loop
• JS do…while Loop
• JS while Loop
• JS for…in Loop
• JS for…of Loop
• JS labeled Statement
• JS break Statement
• JS continue Statement

JS Expression and Operators

You’ll learn the syntax and usage of expressions, which are combinations of values, variables, operators, and functions that produce a result.

• JS Assignment operators
• JS Comparison operators
• JS Arithmetic operators
• JS Bitwise operators
• JS Logical operators
• JS BigInt Operators
• JS String operators
• JS Ternary operator
• JS Comma operator
• JS Unary operators
• JS Relational operators

JavaScript Objects

Objects in JavaScript are complex data types that allow for the creation of structured entities with properties and methods.

• JS Array
• JS String
• JS Date
• JS Number
• JS Math
• JS Object
• JS Boolean
• JS JSON
• JS Map
• JS Set
• JS Atomics
• JS BigInt
• JS Promise
• JS Proxy
• JS Reflect
• JS WeakMap
• JS WeakSet

JavaScript Functions

Functions in JavaScript are reusable blocks of code that perform a specific task.

• JS Functions
• JS Function Definitions
• JS Function Call
• JS Function Expression
• JS Pure Functions
• JS Function Parameters
• JS Function Invocation
• JS Anonymous Functions
• JS Arrow functions
• JS Nested functions
• JS Function Generator
• JS Function binding
• JS Async/Await Function
• Hoisting in JavaScript

JavaScript Regular Expression

Regular expressions, often abbreviated as regex or regexp, are patterns used to match character combinations in strings.

• JS Regular expressions
• JS RegExp [abc] Expression
• JS RegExp S Metacharacter
• JS RegExp m Modifier
• JS RegExp ?! Quantifier
• JS RegExp {X,Y} Quantifier
• JS RegExp test() Method
• JS RegExp [^0-9] Expression

JavaScript Events

Events are actions that happen in the browser, such as mouse clicks, keyboard input, or page loading. This part of the content explores how to work with events in JavaScript, including event handling, event listeners, event propagation, event objects.

• JS Events
• JS onclick Event
• JS dblclick Event
• JS onload Event
• JS onresize Event
• JS onblur Event
• JS onchange Event
• JS Focus Event 
• JS Clipboard Event
• JS onscroll Event

JavaScript OOPs

Object-Oriented Programming (OOP) in JavaScript, a concept that enables the structure of code by modeling real-world entities as objects with properties and behaviors.

• JS Classes In JavaScript
• JS class expression
• JS Object Constructors
• JS Static Methods
• JS Prototype
• JS Constructor Method
• JS Encapsulation
• JS Inheritance
• JS Polymorphism
• JS Abstraction

JavaScript Inheritance and Prototype Chain

Inheritance allows objects to inherit properties and methods from other objects, enabling code reuse and creating hierarchical relationships between objects.

• Prototype Inheritance in JavaScript 
• Prototype Chain in JavaScript
• JS Object Constructors
• JS Prototype in JavaScript

JavaScript Memory Management

JavaScript uses automatic memory management, known as garbage collection, to allocate and deallocate memory dynamically.

• JS Memory Management
• JS Garbage Collection

JavaScript Promises

JS Promises provide a cleaner and more intuitive way to work with asynchronous code compared to traditional callback-based approaches.

• JS Promise
• JS Promise Chaining
• JS Errors Throw and Try to Catch
• JS Class compositions in JavaScript

JavaScript Iterators and generators

Iterators are objects that define a sequence and provide a standard way to access its elements one at a time, while generators are functions that can pause and resume their execution to produce a sequence of values lazily.

• JS Iterator
• JS Function Generator 

JavaScript Validations

JavaScript validations help ensure that data entered by users meets specific criteria, such as format, length, or range, before submitting it to the server.

• JS Form Validation
• JS Email Validation

JavaScript Exception Handling

Exception handling is crucial for ensuring the reliability and stability of JavaScript applications by handling errors effectively

• JS Exception Handling
• JS try-catch Statement
• JS Promises
• JS async/await

JavaScript Global Objects

Global objects play a important role in JavaScript development, offering a wide range of functionalities for various tasks

• JS encodeURI(), encodeURIComponent() and decodeURIComponent() Method
• JS eval() Method
• JS globalThis Property
• JS Global property
• JS Infinity
• JS Undefined vs Undeclared

JavaScript Miscellaneous

This section serves as a repository for miscellaneous JavaScript topics that don’t fit neatly into other categories but are still valuable for JavaScript developers to understand

• JS this Keyword
• JS Strict Mode
• JS setTimeOut() and setInterval() Method
• JS typeOf Operator
• JS Debugging
• JS Local Storage
• JS Callback
• JS Closures
• JS defer
• JS scope
• JS Void

JavaScript Practice Quiz

This section offers a collection of practice Quiz designed to test and support understanding of various concepts in JavaScript.

• Practice Quiz-1
• Practice Quiz-2
• Practice Quiz-3

JavaScript Interview Questions

This section provides a list of interview questions related to JavaScript.

• JavaScript Interview Questions and Answers (2024) For Begineers
• Intermediate JavaScript Interview Questions and Answers (2024)
• Advance JS Interview Questions and Answers (2024) For Experienced

History of javascript

• JavaScript was developed by Brendan Eich in May 1995.
• First name of the JavaScript was Mocha, it later underwent a name change to LiveScript before finally settling on JavaScript.
• In 1997, JavaScript was recognized as an ECMA standard (ECMA-262).
• ECMAScript 6 (ES6), released in 2015.

JavaScript Libraries and Frameworks

JavaScript libraries and frameworks play a important role in modern web development. They offer built-in functions and methods that enhance web pages, making them more dynamic and interactive. They handle repetitive tasks, allowing developers to focus on core functionality.

Also, they provide project structure and data flow structure that helps to create fast and more reliable applications.

JavaScript Libraries

Libraries provide pre-built solutions for common tasks. Developers can leverage these functions instead of writing code from scratch, saving valuable time. Here are a few popular libraries of JavaScript.

• ReactJS
• jQuery
• p5.js
• D3.js
• Collect.js
• Underscore.js
• Lodash
• Tensorflow.js

JavaScript Frameworks

Frameworks, offer a comprehensive structure for building applications. Here are a few popular frameworks of JavaScript.

• AngularJS
• Vue.js
• NuxtJS

If you are a person, who is more into study from Courses. JavaScript Course Provides you Complete Beginner to Advanced learning.

JavaScript Tutorial- FAQs

What versions of JavaScript does the tutorial cover?

This JS tutorial covers a wide range of JavaScript versions, from the basics to more advanced concepts. It encompasses both older versions like ES5 and ES6, as well as more recent versions and features introduced in ES7, ES8, ES9, and beyond.

What is JavaScript used for?

JavaScript is primarily used for enhancing web pages by adding interactivity, dynamic content, and user-friendly features. It runs directly in web browsers and allows developers to create responsive and engaging user interfaces.

How do I learn JavaScript from scratch?

To learn JavaScript from scratch, start with the basics:

• Understand variables, data types, and operators.
• Learn about functions, loops, and conditional statements.
• Practice by building small projects and gradually move to more complex ones.

What are JavaScript frameworks?

JavaScript frameworks (such as Angular, or Vue.js) provide a structured way to build web applications. They offer pre-built components, routing, state management, and other tools to streamline development.

Is this an advanced JavaScript tutorial?

this javascript tutorial covers all important advanced JavaScript concepts such as functional programming, object-oriented programming, asynchronous programming, and more. Beginners can start with the basics and gradually delve into more advanced concepts as they progress through the tutorial.

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